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arXiv · 2101.00927

Twin Mechanical Metamaterials

Wenwang Wu·Seok Kim·Ali Ramazani·Young Tae Cho·Daining Fang
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Abstract

By mimicking the geometrical relation of nano-twin crystals, we propose novel architected twin mechanical metamaterials (TMMs), which can impede local shearing band formation under external loading, thus avoiding global catastrophic failure. The effects of twin-space and twin angle on the mechanical performance of TMMs were also explored, such as: energy absorption, strength, and crack propagation resistance. The results showed that the twin topology design can not only significantly improve the energy-absorption efficiency but also remarkably improve the crack-propagation resistances of stretching-dominant mechanical metamaterials. We also studied the effect of twin-space and twin angle on the tensile strength of TMMs. This study is the first to report on the inverse Hall-Petch effect of TMMs. Our findings open an avenue for the design and fabrication of advanced materials with exceptionally tuneable mechanical properties.

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Wenwang Wu, Seok Kim, Ali Ramazani, Young Tae Cho, Daining Fang. 2021-01-04. Twin Mechanical Metamaterials. https://arxiv.org/abs/2101.00927

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